Can order by and grouping be used together in mysql?

Yes, MySQL allows the use of the ORDER BY clause in grouped queries to sort results. The steps are as follows: Group data (GROUP BY) Aggregate data (use aggregate function) Sort results (ORDER BY)

Combined use of ORDER BY and grouped queries in MySQL

Yes, MySQL allows the use of ORDER BY clause pairs in grouped queries The results are sorted.

Usage:

<code class="sql">SELECT column1, column2, ...
FROM table_name
GROUP BY column_group
ORDER BY aggregate_function(column) ASC/DESC;</code>

Steps:

1. Group data: Use GROUP The BY clause groups data.
2. Aggregate data: Use aggregate functions (such as SUM, COUNT, AVG) to calculate each set of data.
3. Sort results: Use the ORDER BY clause to sort the grouped results.

Example:

Find the total number of employees in each department and sort by the total number of employees from high to low:

<code class="sql">SELECT department, COUNT(*) AS total_employees
FROM employees
GROUP BY department
ORDER BY total_employees DESC;</code>

Note:

• The columns used in the ORDER BY clause must be grouping columns or the result of an aggregate function.
• If aggregate functions are not used, the ORDER BY clause cannot be used in grouped queries.
• The sort order following the grouping column or aggregate function can be ASC (ascending) or DESC (descending).

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